Any savvy readers want to annotate these images to point out different features?

Okaaay...
Without knowing the sub soil structure, or seeing the engineering drawings, it looks like a fairly traditional type of raft construction since there was no mention of piling, where the foundation 'box'(in cross section) additionally provides for service ducts and storm drain functionality.
I would expect(but I don't know) that the required damping support - think earthquakes, will sit atop this below ground structure, for the above ground floors.
Tunnels?...no mystery. Services, cross site access( you can't expect everyone to walk the whole perimeter to see your buddy in another department or walk in the rain) and access to the central underground theatre from various building points. There will also be direct access to the theatre from outside the perimeter for joe public and (especially) the press - who wants them to all be traipsing through reception for presentations?
Apart from that, there's not much that can be said.
Wonder where the snoop-proof room is?

Any savvy readers want to annotate these images to point out different features?

These are not very good photos, but what I gather from what I can make out is that little if any form work has started yet. The blue stuff is rebar which has been staged near where it will be needed. And I can see retaining walls made of steel mesh and tar paper to keep dirt from collapsing into the dug trenches.

I'd say that, before the rebar starts getting laid, there may very well be more excavation. Also, there will be some sort of gravel bed spread out and carefully leveled upon which the rebar will be laid.

You can see it from space! Should have modified the circle into the shape of the Apple logo.

That's a cute idea! But companies do change their logos from time to time, so it would be risky. Not to mention limiting the re-sale value of the property, when Apple decides to relocate headquarters completely to Ireland. Or when they need to downsize (they are doomed, after all).

Fair point. But if they were to build in the shape of an Apple logo, they would be able to move into the leaf bit when they had to downsize due to being doomed.

"If the young are not initiated into the village, they will burn it down just to feel its warmth."- African proverb

When the thing is finally finished and Apple moves in, they’ll obviously dedicate a portion of their first keynote in the new building to the construction of Infinite Loop. And, of course, that will include one of those time lapse montages of construction images.

But we’ll be able to one-up them, as AI will be able to have a time-lapse montage of articles about the construction!

Wouldn't a time-lapse of Infinite Loop create a Black Hole?

"If the young are not initiated into the village, they will burn it down just to feel its warmth."- African proverb